Central and N. Europe were covered with polar desert:
arid tundra with a few plants and animals seasonally.
Farther south steppe tundra: mixture of grassland and tundra plants, with
grazing animals. (biom in Siberia today [Kamarov in: Love, 1988]

DRYAS FLORA: characteristic of the late-Weichsel stadials, its species are
found today in arctic and alpine habitats - they are INDICATORS
of alpine vegetation. The dryas flora is usually preserved in inorganic
sediment at base of bog cores.
Typical Members of Dryas Flora:

Expansion of Birch (Betula) in "preBoreal," followed (9000) by Hazel (Corylus)
the first warmth-requiring tree. It migrated northward from Mediterranean area via
Yugoslavia and Poland
Aridity of the Boreal in part due to greater continentality. Before the isostatic rebound was
complete, The English Channel was above water.
Evidence for warmth

Ivy and Mistletoe, which are very sensitive to freezing
temperatures, were common in Denmark where today they are rare.

Pond tortoise also present. ± 2 oC higher than today

Fauna: Elk, Aurochs, Deer, Boar, humans (stone ax, dog)

8000 - 5000 ATLANTIC: shade-tolerant forest species

Elm, Oak, Lime (=Basswood) and Alder: Quercicetum mixitum become dominant
Hazel and other pioneer trees are shaded out
Very Warm and Moist: Ivy and Mistletoe most abundant, Trapa natans
(Water Chestnut) is present in Denmark.
Fauna: Boar, Deer (sparse)

1948 Published 3-part Neothermal Climatic Sequence based on Great Basin arroyo geomorphology and lake chronologies. Preceded Libby's discovery of radiocarbon dating. Time scale based on Swedish Varve Chronology and the European climatic sequence